It's hot, and I'm in the garden arguing with the tortoise. For most of the winter he's static enough to use as a doorstop, but when the temperature rises above 25C, he becomes surprisingly nimble, even lively, to the extent that he cannot pass a bare foot without taking a bite. This is the subject of our present dispute: he snuck up on me while I was reading the paper and is now eyeing my big toe, his beaky mouth already ajar.

"Don't even think about it," I say. He cranes his neck in preparation. I lift my foot, and he bites at the air.

"Too slow," I say. "That's always been your problem, frankly." I resent the tortoise a bit, because my wife has had him since she was eight and he'll still probably outlive me. I go to the kitchen to get him a plum, carry him to the end of the garden and set it down in front of him.

This, I calculate, will buy me enough time to finish the Sudoku. It is a miscalculation. Minutes later, I feel his jaws clamping down on my toe. I screech and pull back my foot.

"How dare you," I say. The tortoise looks up at me, plum flesh hanging from his chin. Then he turns toward my other foot. "This is unacceptable behaviour," I say, holding both feet off the ground. "You're meant to be vegetarian. I just want to sit here for five minutes and..." I hear a cough and the rustle of a newspaper page being turned. One of our neighbours is sitting in his garden, listening to me talk to an animal that doesn't even have ears. I go inside to put on some shoes.

When the dogs see me putting on shoes, they become excited. Then overexcited. "We're not going anywhere," I say, sitting down on the sofa to do up my laces. "Nothing is actually happening. This is just a precaution so that…" They charge me. The little one leaps into the air and hits me in the chest like a football. The larger one puts its paws on my knees and barks into my face. They start fighting over access, which quickly gets out of hand.

"All right," I say. "I will take you out, but you have to get off."

Once in the park, I start to swerve to make a detour round the drinking bench, where conversation can be confusing and hard to escape, but the man and the woman sitting there – both regulars – are already waving me over. "Morning, mate," the man says. "How you doin'?"

"Fine," I say. "Lovely weather."

"You going for a jog or something?"

I assume he's implying I'm walking past in a hurried, unfriendly way, so I stop. "No," I say. "I was just..."

"I'm gonna buy you some trainers," he says. It takes me a while to process this statement: are we still on jogging? "Are you?" I say.

"Yeah, those are, like, old school." I look down at my feet.

"Well, yeah, I mean, I just put them on quickly because..."

"What's wrong with his shoes?" the woman says. "I like those shoes."

"They's Converse, innit," he says.

"Yes, they are," I say, thinking: but it doesn't mean we have to converse about them. I can see both dogs depositing turds in the tall grass, and take a step in that direction. "I should probably..."

"Don't get me wrong," he says, "Converse is cool, but you need to get the high ones. Those are just..."

"Leave him be," the woman says.

I arrive home half an hour later and kick off both shoes. My footwear is nobody's business but mine, I think. The paper is on the kitchen table. As I sit down to finish the Sudoku, I hear a thunk as the tortoise hauls himself over the threshold.